What is a reverse proxy?

A reverse proxy retrieves resources on behalf of a client from one or more servers, and then returns these resources to the client as though they came from the server itself.

A reverse proxy is located between the client and the proxied server(s). Clients access content through the proxy server. The reverse proxy server assumes the public hostname of the proxied server. The hostname(s) of the actual/proxied servers are often internal and unknown to the client browser.